function externalLinks() {
	if (!document.getElementsByTagName) return;
	var anchors = document.getElementsByTagName("a");
		for (var i=0; i<anchors.length; i++) {
		var anchor = anchors[i];
	if (anchor.getAttribute("href") && anchor.getAttribute("rel") == "external") anchor.target = "_blank";
 }
}
window.onload = externalLinks;

function nullValueOpen() {
	Event.observe("NullValue", "click", function() {
		document.getElementById('nulls').style.visibility = TRUE;
		})
	}       
Event.observe(window, "load", nullValueOpen)